• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.511-518
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• 2017

In recent years, many interests and researches on the insulations required the multiple performances other than insulation performance. The purpose of this paper is to find the optimal ratio between wood fiber and rice-husks charcoal to develop a structural board with carbonized rice-husks. Based on these rice-husks charcoals, basic research was carried out to develop thermal insulation materials with structural performance, and the following conclusions were obtained. The MC of the board using the carbonized rice-husks was 3.2-4.1% and the density was 0.58-0.68, indicating the possibility of excellent structural material. The bending strength was 9.1-32.6 MPa in the length direction and 9.2-34.1 MPa in the width direction. It is possible to obtain the bending strength of the normally used MDF level and to find the possibility of development of the thermal insulation material having the structural performances.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.6
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• pp.616-623
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• 2010

Recently, interests in indoor air quality (IAQ) have been increased; however, a number of researchers have mainly focused on anthropogenic volatile organic compounds (AVOC) emitted from building materials. Therefore, the properties of natural VOC (NVOC) and anthropogenic VOC (AVOC) emitted from wood-based panels was investigated in this work. VOCs emitted from these panels were sampled through Tenax TA/Cabotrap and analyzed by GC-MS and GC-FID. Comparisons were made concerning TVOC, NVOC, and composition ratios of NVOC. It was revealed that TVOC emission rates of midium density fiber (MDF) were the highest. Besides, it was found that emissions of NVOC from wood-based panels were much higher than those of anthropogenic AVOC except for plywood of Oceania timber. It was also observed that the composition ratio of NVOC emitted from plywood of Pinus radiata was the highest as 65% of TVOC. Major NVOC components were monoterpene compounds such as $\alpha$-pinene, $\beta$-pinene, d-limonene, camphene and $\alpha$-terpinene. It was concluded that the composition rates of VOCs emitted from building materials were clearly different according to the raw materials and manufacturing methods.

• Fibers and Polymers
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• v.6 no.1
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• pp.28-34
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• 2005

The purpose of the research was to examine the effect of three different levels of enzyme treatment on the physical characteristics and the end-use suitability of the lyocell fabrics made with four different types of commercial wood pulp. The appropriate enzyme concentration for obtaining an optimum as well as consistent physical characteristics and fabric hand trait was 3 g/l for the concentration levels tested in the present investigation. Weight loss was more affected by higher enzyme con­centration than other physical properties. H2 was least affected by enzyme treatment for all three physical properties and fab­ric hand. 5 g/l concentration exhibited little difference from 3 g/l in the physical characteristics, whereas the KES-FB values indicated a significant loss of fabric hand in most PHV s with the 5 g/l concentration level. Among different garment parame­ters, all four fabric types were relatively inappropriate for the men's slacks (MS) fabric due to the lower hand value of koshi required by the MS parameter. However, despite the relatively low koshi values, high fukurami values required for men's dress shirt (MWDS) resulted in the highest THV among the four garment parmeters. The four fabric types, which represent the usage of four different wood pulps, in general seem to exhibit a higher applicability to women's winter thin dress (WWTD) than women's winter suit (WWS) garment parameter.

• Journal of Plant Biology
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• v.35 no.3
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• pp.211-217
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• 1992

In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Acer sacchan'num seedling in horizontal position. During the transition from primary to secondary growth, tension wood(gelatinous fiber) was gradually developed on the upper side only, And the tension wood formation in the upper side of the horizontal first internode proceeds acropetally from base to apical portion. Some of the anatomical features of tension wood start to be in the primary vascular tissue and a typical tension wood show during the secondary growth, Therefore, the procambium seems to respond to the gravity as well as vascular cambium. For this reason, both procambium and vascular cambium has to regard as the same meristem, On the other hand, the upper side vessels were longer than those of the lower side in the horizontal first internode. The lateral-wall pitting of vessel elements, however, showed no differences between upper and lower sides which have alternate type. The width and height of rayon the upper side of horizontal first internode was larger as compared with the lower side.r side.

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.655-662
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• 2019

This study evaluated the multi-bonding performances of timbers as well as those of reinforcement and timber to obtain data for preparing guidelines regarding the use of timbers as large structural members. For the multi-bonding performances of timbers, four types of bonding surfaces were prepared according to the pith position. For the bonding performances of FRP (fiber-reinforced plastic)/steel plate and timber, a total of 11 types of specimens were produced for the selection of the appropriate adhesive. The bonding performances of the produced specimens were evaluated through a water soaking delamination test, a water boiling delamination test, and a block shear strength test. The test results showed that the bonding strength of the bonding surface according to the pith position was highest in the specimen for which the two sections with the pith at the center of the cross-section on timber and between the bonding surfaces (the tangential and radial sections were mixed) were bonded. Furthermore, the specimens for which the section (radial section) with the pith on the bonding surface of the timber was bonded showed a high delamination percentage. The results of the block shear strength test showed that the bonding section did not have a significant effect on the shear strength, and that the measured wood failure percentage was higher than the KS standard value. The PVAc adhesive showed the highest bonding strength between larix timber and GFRP (glass FRP). Furthermore, the epoxy and polyurethane adhesives showed good bonding strength for CFRP (carbon FRP) and structure steel, respectively.

• Journal of the Korean Wood Science and Technology
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• v.40 no.4
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• pp.244-256
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• 2012

The anatomical characteristics of the ten Indonesian wood species (Gmelina, Jeunjing, Mangium, Durian, Gandaria, Jengkol, Kupa, Mangga, Nanaka and Rambutan) were investigated by optical microscopy. All the species were diffuse-porous with solitary and radial pore multiple. In Mangium, however, tangential pore multiple was observed as well. Tangential diameter of pore was larger than that of radial one except for Jeunjing and Nangka. Nangka showed the largest tangential diameter of pore among the species. Vessel number per $mm^2$ of Mangium, Gandaria and Kupa was higher than that of the other species. Especially Kupa showed highest vessel number. The tangential width of axial parenchyma cell in Gmelina, Mangium, Kupa and Mangga was larger than that of wood fiber, while the other species showed the opposite trend. Mangium was the largest in tangential width of axial parenchyma cell. Rays were homocellular composed only of procumbent cell in Gmelina, Jeunjing and Rambutan. Heterocellular rays composed of procumbent cells in the body and one row of upright and/or square in the margin are observed in Gandaria. Mangium, Durian, Jengkol, Kupa, Mangga and Nangkabody showed heterocellular rays composed of procumbent cells in the body and mostly 1~2 rows of upright and/or square cells in the margin. Crystals occurred in Durian, Gandaria, Jengkol, Jeunjing, Mangga and Rambutan and silica in Jeunjing and Mangga.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.293-300
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• 2011

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.49-52
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• 2002

경량 건축소재는 건축자재의 경량화, 고급화 및 다양화 등의 기능성 건축소재로서 역할을 요구하고 있으며 그 중 대표적인 것으로서는 polyurethane foamd, Cellulose, 무기 fiber 등이 건축소재로 이용되고 있다. Cellulose계의 wood material의 경우 건축폐재, 가로수의 전지나무 및 제재공장에서 발생하는 나무쓰레기, 대패밥 등과 폐신문지 등의 가공 후 폐기물이 발생하고 있으며 이러한 Cellulose계의 물질들은 고유한 습기의 조절능력, 단열특성을 가지고 있으나 Combustibility, rotting, warping 등의 단점을 가지고 있다 이러한 단점을 극복하기 위해 현대생활환경에 접근할 수 있는 새로운 cellulose계의 modification 및 기술적으로 많이 연구되어지고 있다.(중략)

• Proceedings of the Korean Printing Society Conference
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• 2007.11a
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• pp.45-57
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• 2007

Properties of newly developed paper from Red Algae Pulp (RAP) were examined. The paper samples were prepared according tomixing RAP fiber with wood fibers, HwBKP and SwBKP, to form a paper with 60 g/$m^{2}$ in weight. It was prepared in three to four different levels of refining degree and pressure so that it can reveal different bulk level in order to clearly compare the opacity at equivalent bulk for each furnish compositions. printability of RAP fiber revealed superior effect on print through repression and initial ink absorption. Those properties are expected to improve further if printability improvement effect due to smoothness improvement is added.

• Advanced Composite Materials
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• v.16 no.4
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• pp.349-360
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• 2007

Recently, natural fiber reinforced composite is attracting attention and considered as an environmentally friendly material. Usually cellulosic fibers are used to reinforce the composites, but some protein fibers such as silk and wool serve the same purpose. In this paper, we proposed a method of producing artistic composite from artistic fabric by using silk fiber reinforced biodegradable plastic, which is designated as 'silk composite', for reinforcement. In order to expand applications of the silk composite, we performed the compression molding of decorative laminates with woody material, which was selected as a core material, and examined the properties of molded decorative laminates with various content of the silk composite. Since plywood and medium-density fiberboard (MDF) are widely used for decorative laminates, we selected them as core materials. As a result, flexible decorative laminates with high flexural strength were obtained by compounding the silk composite with wood materials.